If your new Riva is the true 3.7v device, you can use any Boge carto on it, really: 2.0Ω (those will run hotter), 2.5Ω, or 3.0Ω (standard--cooler vape).
If your Riva is the older, regulated battery (3.2-3.3v--like the eGo), I recommend the 2.0 or the 2.5Ω Boges. Standard 3.0Ω will run too cool on them.
Good luck!